论文部分内容阅读
采用激光熔覆技术在钛合金表面制备了颗粒增强金属基复合涂层,系统研究了Y_2O_3添加对涂层显微组织和开裂敏感性的影响。实验结果表明,加入少量Y_2O_3能有效促进TiC等增强相的形成,但稀土含量过多则会使涂层的物相构成复杂化。其次,Y_2O_3的加入使熔覆层中气孔和夹杂减少,增强相的形态逐渐细化、分布更为均匀,棱边也更圆润,同时涂层和基底的结合质量提高。和不添加Y_2O_3的涂层相比,添加w(Y_2O_3)=1%涂层表面、中部和近界面处的断裂韧度都有显著提高,且平均断裂韧度提高了20%。当稀土含量继续升高时,断裂韧性反而下降。
The particle reinforced metal matrix composite coating was prepared on the surface of titanium alloy by laser cladding. The effect of Y2O3 addition on the microstructure and cracking susceptibility of the coating was studied systematically. The experimental results show that the addition of a small amount of Y 2 O 3 can effectively promote the formation of TiC and other reinforcing phases. However, if the content of rare earth is too large, the phase composition of the coating will be complicated. Secondly, the addition of Y 2 O 3 reduced the porosity and inclusions in the cladding layer, the morphology of the reinforcing phase was gradually refined, the distribution was more uniform, the edges were more rounded, and the bonding quality of the coating and the substrate was improved. Compared with the coating without Y_2O_3 coating, the fracture toughness at the middle and the near interface was significantly increased and the average fracture toughness increased by 20% when the surface of w_ (Y_2O_3) = 1% coating was added. As the RE content continues to increase, the fracture toughness decreases.